The menus for all buttons and cell entries are activated by right clicking
on them.
Rows (left of tableau)

Highlight Row  changes the background color of every cell
in the row for emphasis (toggles on/off); useful for classroom discussions.

Delete Row  deletes the row from the tableau; one can continue
to pivot in the tableau without errors.

Add Row Before  inserts an empty row into the tableau above
the given row; this is usually done while constructing the original
tableau or modifying a copied tableau (if done after several pivots
then further pivots will most likely not be integral); also useful
when adding cutting planes for integer optimization problems, but
you can add a column simulaneously with the cell button
Add Row and Column After instead.

Add Row After  inserts an empty row into the tableau below
the given row; this is usually done while constructing the original
tableau or modifying a copied tableau (if done after several pivots
then further pivots will most likely not be integral); also useful
when adding cutting planes for integer optimization problems, but
you can add a column simulaneously with the cell button
Add Row and Column After instead.

Fill Row with 0s  enters 0 in each cell of the row;
useful for sparse matrix construction.

Fill Row with 1s  enters 1 in each cell of the row;
useful for problems involving convexity and games.

Mark as Equality  marks the row as an equality by putting a
red E on the row button (toggles on/off);
the E will remain red until a pivot is
performed in the row, at which point it will change to (and remain)
a green E; useful for remembering
to pivot in a basic variable for an equality constraint.
